Mugulg, the Quartermaster
Mostly a tank and spank but she will cast <Battling Resolve> that will heal her for about 2.5 million - interruptable, watch casting-bar and listen to distinct sound. With high damage per second it's unnoticable but can make it very difficult with a duo.

Chef Blarghrot
Mostly a tank and spank but he will cast <Nausea> that will do a high damage AE physical crushing stun - interruptable.

Captain Goldjaw
Mostly a tank and spank but he will have red text come up where he "stares" at someone. That someone is typically safe, but the rest of the group takes heavy physical damage. Not sure how to avoid it yet.

The Tempest of Zek
A tornado looking thing on the main deck. Mostly a tank and spank but he will summon a circle on the ground around someone accompanied by red text with that someone's name. Getting out of the circle avoids the negative consequences - I'm not sure what those are because it's so easy to avoid.